Characterization of the transcriptional regulation of the regulator of G protein signaling 2 (RGS2) gene during 3T3-L1 preadipocyte differentiation

Adipocyte differentiation is a complex process involving several signaling pathways. Molecular mechanisms regulating the very early stage of adipocyte differentiation is not fully appreciated yet. Several inducible genes at the early stage of preadipocyte differentiation have been identified, including the regulator of G protein signaling 2 (RGS2), a member of the RGS protein superfamily. This study aimed to clarify the precise induction profile of RGS2 and to determine the essential transcription element(s) regulating RGS2 expression in differentiating 3T3-L1 preadipocytes. RGS2 mRNA expression was elevated immediately at 1 h after differentiation initiation and it remained high until the late stage of differentiation. The putative promoter sequence (approximately 3,000 bp) of the mouse RGS2 gene was isolated and the RGS2 promoter activity was significantly upregulated 3 h after inducing differentiation. The primary signaling pathway leading to RGS2 transcriptional activation appeared to be cAMP-dependent. Sequential deletion and site-directed mutagenesis strategies demonstrate that the RGS2 promoter sequence truncated down to 78 bp in size retained full inducibility by the differentiation stimuli. Mutation of a Sp1 site within the 78 bp region significantly blocked promoter activity. In addition, high expression of Sp1 transcription factor was noted prior to and paralleling the differentiation process. Taken together, our data suggest that RGS2 transcription is immediately induced via a cAMP-dependent pathway after initiation of 3T3-L1 differentiation and the RGS2 mRNA level remains consistently high throughout the differentiation progression. A Sp1 site within RGS2 promoter appeared to be a crucial response element to regulate RGS2 transcription.

Magnetic ground state and transition of a quantum multiferroic LiCu2O2

Based on resonant soft x-ray magnetic scattering, we report that LiCu2O2 exhibits a large interchain coupling which suppresses quantum fluctuations along spin chains, and a quasi-2D short-range magnetic order prevails at temperatures above the magnetic transition. These observations unravel the fact that the ground state of LiCu2O2 possesses long-range 2D-like incommensurate magnetic order rather than being a gapped spin liquid as expected from the nature of quantum spin-1/2 chains. In addition, the spin coupling along the c axis is found to be essential for inducing electric polarization.

Aligned Er-doped ZnO nanorod arrays with enhanced 1.54 microm infrared emission

Vertically aligned Er-doped ZnO nanorod arrays with sharp and intense 1.54 microm infrared emission have been fabricated on Si substrates through a well controlled spin-coating and annealing process. The synthesis method is advantageous for synthesizing ZnO nanostructures free from structural defects, capability for large-scale production, minimum equipment requirement and product homogeneity. Er atoms were found to incorporate into ZnO lattice from XRD, ESCA, TEM, STEM/EDS and PL measurements. The single-crystal Er-doped nanorods maintained their high microstructural quality after annealing for 4 hr at 800 degreesC. The intensity of 1.54 microm infrared emission was found to be correlated with the deep level green emission. The enhanced luminescence intensity and best ever narrow wavelength distribution of Er-doped ZnO nanorod arrays at 1.54 microm emission will be conductive to applications in optoelectronic devices and optical communications.

Efficacy of a modified improved technique for detecting red cell haemoglobin H inclusions

Alpha-thalassaemia is a common disease in Taiwan. A feature useful in diagnosis is the excess of of beta-chains that result from impaired alpha-chain production. These excess chains assemble into beta 4 tetramers (i.e. Hb H) which can be detected by its rapid anodal migration on alkaline electrophoretic media as seen in Hb H disease. However, this technique cannot, and conventional Hb H inclusion staining rarely can visualize alpha-thalassaemic traits due to small quantities of Hb H formed in these patients. The staining for Hb H inclusion bodies uses brilliant cresyl blue (BCB) or methylene blue (MB) as an oxidant to denature Hb H as intracellular inclusions. We have improved the technique of Jones (who modified the original method in order to obtain enriched young red cells) by prolonging the incubation time from 30 min to 3 h. The sensitivity of this modified improved method was 91% for detecting obligatory alpha-thalassaemic traits as shown in table. No false positive results were seen in beta-thalassaemia or in others. We believe this can be used as a confirmatory test in heterozygous alpha 1-thalassaemia and homozygous alpha 2-thalassaemia.

Comparison of myeloablative and nonmyeloablative hematopoietic stem cell transplantation for treatment of chronic myeloid leukemia

This retrospective study compared outcomes for 81 chronic myeloid leukemia patients who underwent myeloablative or nonmyeloablative allogeneic hematopoietic stem cell transplantation (HSCT). Sixty-five patients received myeloablative HSCT, and 16 patients received fludarabine (Fd), low-dose busulfan (Bu), and antithymocyte globulin (ATG) in nonmyeloablative HSCT. We determined overall survival (OS) and disease-free survival (DFS), as well as the occurrence of acute and chronic graft-versus-host disease (GVHD). The incidences of acute GVHD of grades II to IV were 14.0% and 18.7% for the myeloablative and nonmyeloablative groups, respectively. The incidence of chronic GVHD was significantly higher in the nonmyeloablative group (80% versus 66%). Five-year OS and DFS rates were significantly higher in nonmyeloablative group (70% for both), compared with 56% and 54%, respectively, for the myeloablative group. A univariate analysis, however, revealed a strong but statistically insignificant trend for enhanced overall OS and DFS in the nonmyeloablative group (P = .1 and .07, respectively). A multivariate analysis with the factors of treatment, age, sex, acute and chronic GVHD, and disease status at the time of transplantation revealed that both OS and DFS were significantly higher in the nonmyeloablative group than in the myeloablative group. These findings suggest that nonmyeloablative Fd/Bu/ATG treatment is at least not inferior (and quite probably superior) in terms of patient outcome compared with standard myeloablative therapy. Further larger-scale randomized clinical trials are warranted to clarify the efficacy of this treatment regimen.

Combined treatment with splenectomy and cladribine in hairy cell leukemia in Taiwan: a clinicopathologic study of 5 cases

BACKGROUND

Hairy cell leukemia (HCL) is a rare B-cell lymphoid malignancy that is characterized by the presence of hairy cells in the peripheral blood and bone marrow, pancytopenia and various degrees of splenomegaly. Very few reports have explored the clinicopathologic features and treatment outcome of HCL in Taiwan.

METHODS

Of 33 patients with malignant lymphoma who underwent splenectomy over a 10-year period (1996-2005), 5 cases of HCL were retrospectively studied.

RESULTS

All cases presented with various degrees of splenomegaly. Pancytopenia was noted in 3 cases, and lymphadenopathy in 1. Typical hairy cells with positive tartrate-resistant acid phosphatase stain were noted in 2 cases. Only 3 cases could be diagnosed with HCL based solely on bone marrow findings. In contrast, all spleen specimens had characteristic pathologic features. All patients underwent splenectomy uneventfully, and cladribine was given at a median time of 2 months after splenectomy without significant side effects. Complete remission with durable response was documented in 4 patients (80%) with a median follow-up of 29 months (range, 4-96 months). The last patient experienced partial remission but was only followed up for 4 months.

CONCLUSION

For the HCL patients in this study, splenectomy had a role not only in improving cytopenia but in aiding diagnosis. Cladribine is safe and highly effective for Taiwanese patients and should be considered as first-line treatment for HCL.

Does social participation by the elderly reduce mortality and cognitive impairment?

PURPOSE

This longitudinal study examines the effect of social participation on mortality and cognitive impairment for the elderly in Taiwan.

METHODS

Data were from an elderly population panel in Taiwan 'The Survey of Health and Living Status of the Elderly' 1993-1999. Social participation was defined as paid/unpaid job and participating in volunteer and social groups. Logistic regression analysis was used for predicting the influence of social participation to 6-year mortality and cognitive function impairment, by controlling of socioeconomic status and health-related variables.

RESULTS

The elderly with continuous paid work were more likely to participate in social groups. Having paid or unpaid work at the baseline year could lower the risk of mortality six years later, especially for men. Having unpaid work was associated with a higher risk of impaired cognitive function compared to that of non-workers. Participating in a religious group reduced the risk of mortality for women and participating in political groups reduced the risk of impaired cognitive function for men.

DISCUSSION

Participating in some types of social activities may reduce mortality or cognitive function impairment in the elderly. However, different activities, gender roles and uneven opportunities for work and social group participation may affect the risk of these endpoints.

Inhibition of superoxide anion and elastase release in human neutrophils by 3'-isopropoxychalcone via a cAMP-dependent pathway

1 Chalcone is abundantly present in the plant kingdom and has various biological activities such as anti-inflammatory and antioxidant. In this study, the semisynthetic chalcone derivative, 3'-isopropoxychalcone (H2O7D), was demonstrated to inhibit the generation of superoxide and the release of elastase, as well as to accelerate resequestration of cytosolic calcium in formyl-L-methionyl-L-leucyl-L-phenylalanine-activated human neutrophils. 2 H2O7D displayed no antioxidant or superoxide-scavenging ability, and it failed to alter the subcellular NADPH oxidase activity. 3 H2O7D induced a substantial increase in cAMP but not cGMP levels. The elevation of cAMP formation by H2O7D was inhibited by adenosine deaminase (ADA). Furthermore, The inhibitory effects of H2O7D were reversed by protein kinase (PK)A inhibitors, as well as ADA and a selective A2a-receptor antagonist. 4 H2O7D inhibited phosphodiesterase (PDE) activities, but it did not alter adenylyl cyclase and soluble guanylyl cyclase activities. These results show that the cAMP-elevating effect of H2O7D results from the inhibition of PDE activity and not from the stimulation of cyclase function. Consistent with this, H2O7D potentiated the PGE(1)-caused inhibitory effects and cAMP formation. 5 In summary, these results indicate that the inhibitory effect of H2O7D is cAMP/PKA dependent, and that it occurs through inhibition of cAMP PDE, which potentiates the autocrine functions of endogenous adenosine. Inhibition of respiratory burst and degranulation in human neutrophils may give this drug the potential to protect against the progression of inflammation.

Complex karyotypes confer a poor survival in adult acute myeloid leukemia with unfavorable cytogenetic abnormalities

Cytogenetics represents the most valuable predictor for a poor outcome in patients with acute myeloid leukemia (AML), but it encompasses a heterogeneous patient population who might have diverse pathogenesis and clinical courses. In particular, the significance of complex chromosome aberrations within this cohort has seldom been addressed before. We analyzed 48 AML patients with adverse-risk cytogenetics in this study. The complex karyotype (three or more numerical/structural cytogenetic changes; 29 patients) was found to occur more frequently among the elderly than a noncomplex adverse karyotype (19 patients; median age, 71 vs. 48; P = 0.005). The patients' performance status was the sole independent factor determining the complete remission rate among patients receiving standard induction chemotherapy. On survival analysis, two factors independently predicted a longer overall survival: noncomplex karyotypes [vs. complex karyotypes, hazard ratio (HR) 0.434, 95% confidence interval (CI) 0.189-0.994, P = 0.048] and achievement of complete remission [(CR) vs. CR not reached, HR 0.170, 95% CI 0.051-0.572, P = 0.004)]. In conclusion, among AML patients with adverse cytogenetics, complex chromosomal aberrations occurred more frequently among the elderly and predicted a poor outcome. These patients should be considered as a unique entity and be separated from those with a noncomplex adverse cytogenetic change. Exploring the underlying mechanisms of leukemogenesis could improve the therapeutic outcome for this group of patients.

Familial aggregation of metabolic syndrome among the Chinese: report from the Chin-Shan community family study

Genetic study on metabolic syndrome is a great challenge, due to its complex traits and the pleiotropic manifestation of atherosclerosis. Familial aggregation and recurrence risk ratio can provide the insight of possible genetic mechanism. The Chin-Shan community family study was based on adolescent probands and their relatives (1356 subjects) who were recruited from one junior high school in the community. Structured questionnaires and biochemical measures were obtained in standard procedures. Definition of metabolic syndrome was followed using the criteria defined by the third adult treatment panel, with a modification of the criteria for adolescent and Asian population. Grandmothers had the highest frequencies (70%) in metabolic syndrome and various atherosclerotic risks. Three factors were found and thus explained 68% of the overall variance. Estimated heritability was the highest in LDL and cholesterol factor (0.36 and 0.40), then blood pressure/obesity factor (0.27), and insulin resistance/dyslipidemia (0.27). Recurrence risk ratio among siblings was 2.95 (95% confidence interval [CI]: 1.39-6.26). The adjusted odds ratio (OR) of proband's metabolic syndrome status was 1.99 (95% CI: 1.08-3.66). The adjusted odds ratios for the three factors for predicting metabolic syndrome were all significant, with highest risk in blood pressure/obesity factor (OR: 1.27, CI: 1.22-1.33), then insulin resistance/dyslipidemia (OR: 1.29, CI: 1.16-1.23). This study demonstrated clearly familial aggregation and recurrence risk ratio of metabolic syndrome and components among the general ethnic Chinese population in Taiwan.

Epitaxial Growth of InN Films by Molecular-Beam Epitaxy Using Hydrazoic Acid (HN3) as an Efficient Nitrogen Source

Epitaxial InN films have been successfully grown on c-plane GaN template by gas-source molecular-beam epitaxy with hydrazoic acid (HN3) as an efficient nitrogen source. Results in residual-gas analyzer show that the HN3 is highly dissociated to produce nitrogen radicals and can be controlled in the amounts of active nitrogen species by tuning HN3 pressure. A flat and high-purity InN epifilm has been realized at the temperature near 550 degrees C, and a growth rate of 200 nm/hr is also achieved. Moreover, the epitaxial relationship of the InN(002) on the GaN(002) is reflected in the X-ray diffraction, and the full-width at half-maximum of the InN(002) peak as narrow as 0.05 degrees is related to a high-quality crystallinity. An infrared photoluminescence (PL) emission peak at 0.705 eV and the integrated intensity increasing linearly with excitation power suggest that the observed PL can be attributed to a free-to-bound recombination.

Interleukin-1 alpha polymorphism has influence on late-onset sporadic Parkinson's disease in Taiwan

Inflammatory events may contribute to the pathogenesis of Parkinson's disease (PD) and interleukin 1 (IL-1) may exert both neurotoxic and neuroprotective effects. We conducted a case-control study in a cohort of 493 PD cases and 388 ethnically matched controls to investigate the association of IL-1alpha C-889T and IL-1beta C-511T polymorphisms with the risk of PD. No significant difference in the genotype distribution of the analyzed polymorphisms was found between PD and controls. However, after stratification by age, individuals over 70 years of age carrying IL-1alpha-889 C/T genotype demonstrated a significant decrease in risk of developing PD (OR = 0.44; 95% CI = 0.22-0.88, p = 0.021) and the decrease is strengthened by IL-1beta-511 T-carrying genotype (OR = 0.28; 95% CI = 0.11-0.71, p = 0.008). Our data suggest that IL-1alpha, acting synergistically with IL-1beta, plays role in PD susceptibility among Taiwanese people older than 70 years of age.

Evaluation of different bonded investments for dental titanium casting

The properties of several different investments were investigated including phosphate bonded, magnesia bonded, and alumina cement investments. Measurements included the setting expansion, thermal expansion, and compressive strength of investments, as well as the tensile strength, elongation, Vickers hardness (VHN) and surface roughness of titanium castings. For phosphate bonded investment, the setting expansion after being mixed with its own mixing solution was 2.10%, which was larger than the other investments; the thermal expansion was -0.25% at 200 degrees C, the compressive strength 14 and 5 MPa after heating. For titanium cast in phosphate bonded investment, the hardness on its top surface was 655 Hv, the tensile strength was 379 MPa, the elongation was 19.4%, and the surface roughness was 2.29 microm. Athough the thermal expansion of phosphate bonded investment is small, the setting expansion is large enough to compensate for the shrinkage of titanium castings. As its thermal expansion at T >/= 600 degrees C was constant and its heating-cooling cycle was almost reversible, these two properties can reduce the thermal shock and thus avoid cracking of the investment.

Role of interleukin-8 and growth-regulated oncogene-α in the chemotactic migration of all-trans retinoic acid-treated promyelocytic leukemic cells toward alveolar epithelial cells*

OBJECTIVE

Although all-trans retinoic acid (ATRA) can treat acute promyelocytic leukemia (APL), it also causes retinoic acid syndrome with presentations similar to acute respiratory distress syndrome. We investigated the role of interleukin (IL)-8 and growth-regulated oncogene (GRO)-alpha in the chemotactic transmigration of ATRA-treated NB4 (ATRA-NB4) APL cells toward A549 alveolar epithelial cells.

DESIGN

An in vitro human cell culture study.

SETTING

University hospital research laboratories.

SUBJECTS

NB4 and A549 cells.

INTERVENTIONS

NB4 and A549 cells were separately cultured with ATRA and/or dexamethasone for 1-3 days. NB4 or ATRA-NB4 cells were then placed in an upper insert and co-incubated with A549 cells or their conditioned medium located in a lower plate.

MEASUREMENTS AND MAIN RESULTS

ATRA stimulated NB4 cells to transmigrate toward the A549 cells in a time- and dose-dependent manner. Replacement of A459 condition medium by its original medium abrogated this transmigration. Only A549 cells constitutively secreted GRO-alpha, and both A549 and NB4 cells constitutively secreted IL-8, which was enhanced by ATRA. Exogenous administration of IL-8 or GRO-alpha also promoted the ATRA-NB4 transmigration. The binding assay demonstrated that ATRA-NB4 cells bound IL-8, but not GRO-alpha, more avidly. Pretreatment with antibodies directed against IL-8 and GRO-alpha receptors reduced ATRA-NB4 transmigration by about 60%. Dexamethasone did not suppress their IL-8 secretion and transmigration in ATRA-NB4 cells, but when applied to A549 cells, IL-8 secretion was suppressed but not GRO-alpha secretion, and there was attenuation of ATRA-NB4 transmigration.

CONCLUSIONS

IL-8 and GRO-alpha secreted from alveolar epithelial cells play an important role in the cell-cell interaction involved in the chemotactic transmigration of ATRA-treated APL cells toward alveolar epithelial cells.

Pathogenetic role of JAK2 V617F mutation in chronic myeloproliferative disorders

The molecular pathogenesis of chronic myeloproliferative disorders (MPDs) is poorly understood. The hematopoietic progenitor cells of patients with polycythemia vera (PV) or essential thrombocythemia (ET) are characterized by hypersensitivity to hematopoietic growth factors and formation of endogenous erythroid colonies. Recently, 4 groups reported almost simultaneously Janus kinase 2 (JAK2) V617F mutation in more than 80% of PV patients, 30% of patients with ET and in about 50% of patients with idiopathic myelofibrosis. The identification of the JAK2 mutation represents a major advance in the understanding of the molecular pathogenesis of MPDs that will likely permit a new classification and the development of novel therapeutic strategies for these diseases.

Nucleotide changes around the splicing acceptor of intron 24 in the factor VIII gene and its impact on splicing

Nucleotide 6724 of the factor VIII gene harbors a polymorphism of low frequency. A report from Taiwan claimed that 97.9% of the 83 alleles examined were of the A nucleotide at this position, which is quite different to the data from Western populations. Furthermore, this nucleotide is the start of exon 25, located in juxtaposition to the splicing acceptor of intron 24. We wonder if the nucleotide change at this location might have any effect on the splicing process of pre-mRNA. Using genomic DNA with direct sequencing of the polymerase chain reaction-amplified intron 24/exon 25 junction site, we found that 59 of the 60 patient samples were of the GTG sequence at nucleotides 6724-6726. The polymorphism is similar between populations in Taiwan and Western countries. The sequence of intron 24 around the splicing acceptor was always TCCAACTCTATTGCCCTCAG (-20 to -1), except for one hemophiliac patient who had a mutation in which the absolute consensus AG doublet of the intron 24 splicing acceptor changed to the AA dinucleotide. Owing to the mutation, exon 24 was erroneously spliced to exon 26, and exon 25 was skipped. This finding further testifies to the importance of the invariant AG dinucleotide in the example of the factor VIII gene.

Three-dimensional conformal radiotherapy for the treatment of arteriovenous shunting in patients with hepatocellular carcinoma

The objective of this study is to evaluate the efficacy of radiotherapy for the treatment of arteriovenous shunting (AVS) in patients with hepatocellular carcinoma (HCC). Between November 1997 and April 2005, 20 HCC patients with AVS were referred to our department for radiotherapy. The radiation was delivered with 10-15 MV X-ray given 5 days per week at 2 approximately 2.5 Gy per fraction. Total doses ranged from 45 to 64 Gy (median dose 60 Gy). The patients were followed up with color Doppler sonography. When non-invasive imaging suggested obliteration, X-ray angiography was performed to verify the results. Four of the 20 AVS proved to be completely obliterated at X-ray angiography in 1.9, 2.8, 1.8 and 2.9 months after radiotherapy. One of the remaining 16 showed obvious regression on Doppler sonography 0.5 months after radiotherapy, but X-ray angiography was not performed to verify the result. Radiation-related hepatic failure did not occur during the follow-up period. In conclusion, radiotherapy is a treatment alternative for AVS in HCC patients and gives patients with poor prognosis the chance to receive further transcatheter arterial embolization.

Characteristics and predictive factors of early-onset diarrhoea during pelvic irradiation

This study reported characteristics and predictive factors of early-onset diarrhoea in patients receiving pelvic irradiation. We retrospectively reviewed 229 patients undergoing radiotherapy alone for cervical or uterine cancer. Oral barium was taken 90 min before simulation. According to contrast medium within small intestine only or colon in simulation films, we categorised patients as normal and rapid transit groups. Small or large volume of small-bowel was also evaluated according to barium distribution of simulation films. Whole-pelvic irradiation (39.6-45 Gy/22-25 fractions) was delivered to all patients initially. We recorded the onset of diarrhoea during pelvic irradiation. The rates of early-onset diarrhoea (<10 Gy) were compared between these two groups. The incidence of diarrhoea before 10 Gy was 7% and 17% (p = 0.138) in patients with normal and rapid transit, respectively. In multivariate analysis, interaction among rapid transit, prior abdomen operation and large small-bowel volume (p = 0.019) were noted for early-onset diarrhoea. Further subgroup analysis revealed that rapid transit (p = 0.046) was a significant factor in patients with both prior abdominal operation and large small-bowel volume. The incidence of early-onset diarrhoea was as high as 40% in this particular group. Patients experiencing early-onset diarrhoea had a higher incidence of moderate to severe diarrhoea (65%) than those without early-onset diarrhoea (23%) (p<0.001). In multivariate analysis, early-onset diarrhoea was the only factor of moderate to severe diarrhoea (p = 0.001). In conclusion, rapid small-bowel transit may be predisposed to early-onset diarrhoea during pelvic radiotherapy in patients with both prior abdominal operations and large small-bowel volume. Early-onset diarrhoea is considered as a predictive factor of diarrhoea of a higher grade.

Influence of methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism, B vitamins and other factors on plasma homocysteine and risk of thromboembolic disease in Chinese

BACKGROUND

Thromboembolic disease is a major cause of morbidity and mortality in many countries. Our previous study found that Chinese subjects carried the same polymorphism of the methylenetetrahydrofolate reductase (MTHFR) gene as described in Western studies. The aim of the present study was to determine the influence of MTHFR polymorphism, B vitamins and other factors on plasma homocysteine (Hcy) levels and risk of thromboembolic disease in Chinese.

METHODS

One hundred and six subjects were enrolled into the study. They were categorized into 4 groups: healthy individuals (n = 42); those with diabetes mellitus (n = 20); those with deep vein thrombosis (DVT) (n = 11); and those with coronary artery disease (CAD) (n = 33). Plasma levels of folic acid, vitamins B6 and B12, Hcy, and fasting blood sugar were measured; total cholesterol, triglycerides, complete blood count, and 677 C-->T mutation in MTHFR were determined.

RESULTS

Plasma Hcy was lowest in the healthy subjects, higher in diabetics, followed by patients with DVT, and highest in patients with CAD (p < 0.001, ANOVA). MTHFR C677T polymorphism was the common factor affecting plasma logHcy levels in all 4 groups of subjects. Triglycerides affected plasma logHcy in the CAD patients. For the 4 groups as a whole, MTHFR polymorphism, triglycerides, and vitamin B12 were the most significant factors influencing plasma Hcy.

CONCLUSION

We suggest that high plasma Hcy is an important risk factor for CAD. Other factors including MTHFR polymorphism, vitamin B12, triglycerides, total cholesterol, and gender might affect Hcy levels in different diseases and conditions.